Flow of electricity: Open versus Closed Circuit

MitsuShai

I need help understanding this conceptually, so can anybody please correct me and help me understand this?
If I'm correct then just say so.


Diagram: http://i324.photobucket.com/albums/k...E/labVpic3.jpg
the circles are bulbs


Ok so the basically in an open circuit there is no flow and in a closed circuit there is flow.

Question 1 : When the switch is closed what happens to the Resistance between P & Q?
Well the resistance is smaller because there is more flow in closed circuit. The bigger the flow the smaller the resistance.

Question 2: What's bigger the resistance to battery in a closed or open switch?
In a open switch, because there is less flow in the circuit. The smaller the flow, the bigger the resistance.

Question 3: How does closing the switch effect the flow of electricity from battery?
Well, this one I can't come up with an answer because the flow out of the battery should be the same regardless of the switch right? And if you look in the diagram only part of the circuit is cut off from an open switch, so in an open switch the flow would be from B to P to A to Q then back to the battery. And in a closed switch bulb C is added, so the paths are different. However, in both paths the same amount of flow is going through the circuit right?

Question 4: What is the brightness of bulb B when switch is closed to open?
Well the switch does not effect bulb B, only bulb C, so there would be no difference.

Question 5: In a closed circuit, what is the brightness of bulb B compared to bulb C?
Bulb B would be brighter because C and A are parallel, so the flow from the battery is split in half equally between the two components, however bulb B has the full flow from the battery. Therefore B would be brighter than C.




Also can someone help me with this too: http://www.physicsforums.com/showthread.php?t=482028

MitsuShai

nevermind, I understand now. :)